HKM-3658963 Black Compact 16 x 4.0 Fat Tire E-Bike Tips the Scales at 63.7 lb with 60 Nm and a 700W Rear Hub Motor

700W · 720Wh · 21 mph · 16 x 4.0 · 60 Nm · Shimano 7-speed · 30 degree climb · 63.7 lb · cable discs

Seventy Pounds of Bike That Still Fits in a Small Car TrunkA Light Build That Grips and Holds

A light 16-inch fat bike with a 700W hub, 60 Nm of torque and a 48V 15Ah pack worth 720Wh in the frame. A 21 mph top speed, a listed 30 degree climb, Shimano seven-speed gears, mechanical discs at both ends and knobby 16 x 4.0 tires. It weighs 63.7 lb, which is what makes it practical as a first e-bike or a second bike that goes in the back of a car. A cage rack sits behind the bench, the headlamp is a round unit in a black housing.

The frame is a compact black loop with a battery box in the middle and a bench that runs back over the rear wheel to a small cage rack. The headlamp is a round unit in a black housing on the fork crown, and the only colour on the bike comes from the red springs on the rear shocks and the orange reflectors in the spokes. Up close the welds look clean and the cable runs are tidy, which is not always the case at this price.

At 63.7 lb it is about ten pounds lighter than the other 16-inch bikes here, and that difference shows up in the way it handles: it is easier to lift onto a rack, easier to pick up after a fall and less intimidating for a rider who has not had a motor between their legs before. The trade is a slightly stiffer frame feel.

At a Glance

• 700W Rear Hub — 48V, 60 Nm of torque
• 48V 15Ah Pack — 720Wh in the frame
• 21 mph Top Speed — Listed figure
• 30 Degree Climb — Listed figure
• Shimano 7-Speed — Trigger shifter at the right grip
• Mechanical Discs — Front and rear, cable actuated
• 16 x 4.0 Tires — All-terrain knobby casing
• 63.7 lb — Light for a fat e-bike
• Twin Rear Shocks — Red springs under the bench
• Cage Headlamp — Round unit in a black housing
• Small Cage Rack — Behind the bench
• Black Finish — Red springs, orange reflectors

Black Frame and Sixteen Inch Tires

The frame is a compact black loop with a battery box filling the space between the top and down tubes and a bench that runs from the seat tube back over the rear wheel. A small cage rack sits behind the bench, and the headlamp is a round unit in a black housing bolted to the fork crown.

The wheels are 16 x 4.0 knobbys on spoked rims with orange reflectors laced into the spokes. Sixteen inches keeps the standover height low and the bike short enough to fit in a hatchback, and the fat casing is what lets it roll over gravel and snow instead of sinking into them.

Suspension is a short-travel fork up front and two coil shocks under the bench at the rear, with red springs and exposed damping. Brakes are mechanical cable discs on both wheels, with a barrel adjuster at the lever so you can take up pad wear without tools.

• Frame: compact loop, black
• Battery: 48V 15Ah, in the frame
• Wheels: 16 in spoked, 4.0 knobby
• Fork: short travel
• Rear: two coil shocks, red springs
• Brakes: mechanical cable disc

Fitted as shipped: the caged headlamp, front and rear fenders, the rear cage rack, a kickstand and the pedals. The bars carry the throttle, the assist switch and the brake levers, and the frame carries the charge port on the side of the battery box.

700W and 720Wh

The motor is a 48V 700W brushless rear hub with 60 Nm of torque and a listed 30 degree climb, which on a 63.7 lb bike is a better power-to-weight ratio than the heavier 16-inch builds. The top speed is listed at 21 mph. A Shimano seven-speed derailleur sits behind it, so a rider can pedal with the motor rather than against it.

The pack is 48V 15Ah, 720Wh, and it lives in the frame. The listed range is 16 to 30 miles, which is narrower than the poster figures for similar bikes, and it is the more honest pair of numbers: 30 is a light rider at low assist on flat ground, 16 is a heavier rider using the throttle. Acceleration is smooth from a standstill.

Because the bike is light, the same 720Wh goes further than it does on a 74 lb build, and the motor has less mass to accelerate. That is the argument for this bike over its heavier siblings: a smaller rider gets a machine they can actually handle, without giving up the fat tires or the suspension. The torque curve stays flat through the midrange.

Who It Fits and How It Rides

The bench is low and the bars are high, so it suits a shorter or younger rider: both feet reach the ground and the reach to the bars is short. At 63.7 lb one adult can lift it onto a rack, which is not true of the 20-inch bikes. A tall rider will find the cockpit cramped.

On gravel, grass and snow it is stable and the twin rear springs take the chatter, and the fat casing floats where a narrow tire would dig in. On pavement the knobbys hum and the small wheels feel busy above 15 mph. It is at its best on a campground loop, a rail trail or a beach path.

• Campground loops and rail trails
• Gravel, grass and snow
• A first e-bike for a shorter rider
• Not for tall riders or long road rides

What's in the Box

Before the first ride: fit the front wheel and torque the axle, set the bars square to the fork, set the rear spring preload for the rider's weight, bed the cable discs in with ten firm stops and charge the pack. Budget 30 to 45 minutes.

Color and Finish

Black covers the frame, battery box, fenders, bench, rack, fork and rims. The red is in the two rear springs, and the orange reflectors in the spokes are the only other colour on the bike. It is a deliberately plain build with no decals beyond the small frame badge.

Touch-up paint in satin black is available on request. The wear points are the battery box where a shoe rubs it, the cage rack edges and the frame loop above the pedals.

Battery Care and Maintenance

Charge between 20 and 90 percent for everyday use and take it to full about once a month. The pack lives in the frame, so charge it where the bike is stored and keep that spot above freezing. If the bike will sit for a month, leave it around half charge and top it up every few weeks.

Check tire pressure before every ride at 15 psi on pavement and 8 on gravel, and check the spokes and axle nuts after the first 50 miles. The cable discs need the barrel adjuster turned as the pads wear, and the pads are a five-minute swap. Keep the chain oiled so the seven gears shift, and wipe the fork legs after a wet ride.

Specifications

Frequently Asked Questions

Service and Policies

Coverage that lasts beyond the box. Orders ship free with a tracking number in 2 to 5 business days. From delivery, the product is protected for 180 days against manufacturing defects and transit damage, returnable within 30 days for a full refund, and covered by a 24-month parts-and-labor warranty on manufacturing defects. Four policies, one idea: ship it free, protect it for 180 days, take it back for 30, and stand behind it for two years.

HKM-3658963 · compact 16 inch fat tire electric bike · 48V 700W brushless rear hub with 60 Nm and a 30 degree climb · 48V 15Ah 720Wh pack in the frame · 16 to 30 miles listed range · 21 mph top speed · mechanical cable disc brakes front and rear · short-travel fork with two red coil shocks under the bench · 16 x 4.0 all-terrain knobby tires on spoked rims · Shimano 7-speed drivetrain · 63.7 lb, 28.9 kg · caged round headlamp, rear cage rack and fenders · black with red springs · charger in the box · UL listed · built for campgrounds, rail trails and gravel rather than long road rides · one adult can lift it onto a rack at 63.7 lb. Every figure here comes from the product data.